United States securities and exchange commission logo March 11, 2021 Joseph P. Hagan Chief Executive Officer Regulus Therapeutics Inc. 10628 Science Center Drive, Suite 225 San Diego, CA 92121 Re: Regulus Therapeutics Inc. Registration Statement on Form S-3 Filed March 10, 2021 File No. 333-254063 Dear Mr. Hagan: This is to advise you that we have not reviewed and will not review your registration statement. Please refer to Rules 460 and 461 regarding requests for acceleration. We remind you that the company and its management are responsible for the accuracy and adequacy of their disclosures, notwithstanding any review, comments, action or absence of action by the staff. Please contact Ada D. Sarmento at 202-551-3798 with any questions. Sincerely, Division of Corporation Finance Office of Life Sciences cc: Thomas A. Coll, Esq.